Numerous fence designs have been produced for the cutting tables of various cutting tools such as woodworking table saws. The fence on a table saw is used, in general, to hold an edge of a workpiece at a specific angle, usually parallel to a cutting blade 13. The fence must be held parallel to the blade to minimize the kerf width, and to avoid dangerous “kick-back.” A precisely parallel fence also is a significant factor in cutting accuracy.
Much of recent development in design of fences for cutting tables has focused on accuracy, or the ability for the fence to maintain an accurate state of parallelism with the saw blade. However, a high degree of accuracy has not been maintained, at least not without involving complex and difficult to install mechanisms. Such mechanisms most often result in a practically permanent installation of the fence on the saw, since removal and remounting of the fence is most often a laborious, time consuming chore.
An example of a high quality, accurate retrofit fence for table saws is described in U.S. Pat. No. 4,521,006 to Waters. This fence makes use of pulley mounted cables that extend in an endless loop along opposite sides and across one end of the saw table. Two flights of the cable run parallel to each of the front and back edges of the table. Two of the four flights move in the same direction as the cable is moved about the pulleys. Blocks are secured to these parts of the cable. The blocks are releasably mounted to locking devices provided at opposite ends of the fence cutting guide. Two clamping levers are used to secure the fence to “L” shaped brackets that are bolted to the table. In order to remove the fence from the table, the blocks must be moved laterally toward the table, away from engagement with the locking levers. This requires the user to reach under the fence, shift one block from engagement with the associated locking lever, then walk around the saw and perform the same steps to remove the remaining block from the lever on that side of the table. Now the fence may be removed, but only by sliding it off an end of the table. Remounting the fence involves the above operation in reverse.
U.S. Pat. No. 2,805,479 to Droste discloses a work table for sheet materials in which opposite ends of a fence-like bar are mounted to cables that extend about pairs of pulleys. The pulleys are rotatably mounted at ends of the table. Two of the pulleys are interconnected by a drive shaft for rotation in unison. Thus rotation of the shaft will cause corresponding substantially equal motion of the cables about the pulleys. The fence spans the table, with ends clamped to the cables by screw and nut combinations. The fence may be removed by loosening the clamps.
The above examples of cable and pulley mounted fences operate well to hold a fence in accurate position on across a table surface, but both are relatively complex. Also neither of the above apparatus are easily removable from the cutting table when use requires removal of the fence.
It is therefor an object of the present invention to provide a cutting table fence that is simple in construction, easy to mount to an existing cutting table, and which includes a cutting guide that is easily removable from the table.
The above and still further objects and advantages will become apparent from the following description which, taken with the accompanying drawings, disclose a preferred form of the present invention.